21280640

素因数分解:

$2^7\times 5^1\times {\mathrm{41}}^1\times {\mathrm{811}}^1$

素因数の和:871

約数の個数: 64

約数和(自身を含む): 52179120

約数和(自身を除く): 30898480

約数列:

[1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 41, 64, 80, 82, 128, 160, 164, 205, 320, 328, 410, 640, 656, 811, 820, 1312, 1622, 1640, 2624, 3244, 3280, 4055, 5248, 6488, 6560, 8110, 12976, 13120, 16220, 25952, 26240, 32440, 33251, 51904, 64880, 66502, 103808, 129760, 133004, 166255, 259520, 266008, 332510, 519040, 532016, 665020, 1064032, 1330040, 2128064, 2660080, 4256128, 5320160, 10640320, 21280640]

約数ペア:

[(1, 21280640), (2, 10640320), (4, 5320160), (5, 4256128), (8, 2660080), (10, 2128064), (16, 1330040), (20, 1064032), (32, 665020), (40, 532016), (41, 519040), (64, 332510), (80, 266008), (82, 259520), (128, 166255), (160, 133004), (164, 129760), (205, 103808), (320, 66502), (328, 64880), (410, 51904), (640, 33251), (656, 32440), (811, 26240), (820, 25952), (1312, 16220), (1622, 13120), (1640, 12976), (2624, 8110), (3244, 6560), (3280, 6488), (4055, 5248)]